German WW2 10.5 CM SKC 32M Naval Kriegsmarine Artillery Shell.
The 10.5 cm SK C/32 (SK - Schiffskanone (ship board cannon), was a widely used German naval gun on a variety of Kriegsmarine ships during World War II. Originally designed as a surface weapon, it was used in a number of other roles such as anti-aircraft and coastal defence; wet-mounts were developed for U-boats.